Behavior of Low Alkali Concrete Exposed to Seawater in Long-Term Case Study Farø Bridge-Denmark

Abstract

Corrosion of concrete is one of the main causes of destruction of concrete structures, reducing the aesthetics of the building as well as its usability. The current corrosion research is mainly based on experimental research based on actual construction so it is difficult to predict the problems of concrete corrosion for a specific building when it is put into use. The paper uses a numerical model to study the degradation mechanisms that cause damage to a concrete bridge named Farø Bridge-Denmark. The numerical results show that hydrated cement minerals are unstable in seawater, except for hydrotalcite. Minerals harmful to concrete such as Chrysotile (M-S-H) and Thaumasite are precipitated, along with the precipitation of calcite when carbonate ions are present in seawater. The formation of these minerals reduces porosity and can cause microcracks in concrete. Numerical model studies successfully the degradation mechanisms of concrete corrosion caused by seawater in the long term.